Field of the Invention
The present invention relates generally to the control of electromagnetic interference (EMI) and specifically to an apparatus for making electrical connection to a device containing electronics requiring EMI protection. Electromagnetic interference is said to exist when unwanted voltages or currents are present so that they adversely affect the performance of a device or system. These voltages or currents may reach the victim circuit by conduction or by radiation. Electrical filters may be designed to offer little opposition to the passage of certain frequencies or direct current (dc) while blocking the passage of other frequencies. Filters play a significant role in the reduction of conducted interference. A metal barrier may be imposed between sources of electrical noise and their victims to reduce or eliminate the electrical interference due to radiated interference.
The present invention is described in the environment of a pressure sensor or pressure transducer application. However, it is to be understood that this is only an illustrative environment and the present invention applies to other applications as well.
A transducer transforms one form of energy into another form. For example, a transducer can covert the measure or value of some physical property such as pressure or temperature into a corresponding value of an electrical parameter such as voltage. Transducers typically include extensive electronics to reliably manipulate or process very low level electrical signals. Therefore, it is necessary to take precautions in the design to minimize the effects of EMI on the transducer electronics. Transducers, for example precision pressure transducers, are applied in a wide variety of industrial and other applications in which the associated wiring or cabling is routinely exposed to EMI from many sources. In the past, electrical filtering arrangements including electrical components provided on a separate board specifically designed to reduce EMI have been employed in pressure transducers. In the past, EMI shielding of the EMI board circuitry has been provided by using additional parts for shielding. The extra parts add both piece part and labor costs. Thus, there is a need for an improved apparatus for making electrical connections to a device containing electronics requiring EMI protection.